1. Field of the Invention
The present invention relates to a metal waveguide device, and nano plasmonic integrated circuits and an optical integrated circuit module using the same. More particularly, the present invention relates to a nano plasmonic integrated circuit module for converting optical signals into surface plasmon polariton (SPP) signals, transmitting the converted SPP signals, and sensing and processing the transmitted SPP signals.
2. Description of the Related Art
Recently, it has been experimentally confirmed that when a metal and a dielectric satisfy specific conditions at the boundary therebetween, optical waves interact with free electrons on the surface of the metal thus causing resonance. This resonance corresponds to resonance between the electromagnetic waves outside of the metal and the free electrons of the metal. Such resonance produces surface plasmons which are progressive waves of high-density electrons similar to when water waves travel along the surface. The surface plasmons or the SPPs indicate that light or photons travel along the surface in the form of being coupled with plasma at the interface between the metal and the dielectric.
If the optical waves incident in a transverse magnetic polarization mode on the interface between the metal and the dielectric satisfy a phase-matching configuration through an appropriate process, electron motion, namely plasma, may be caused on the surface of the metal, resulting in a near field on the interface between the metal and the dielectric. The surface plasmon waves may be made to have a magnitude of tens of μm or more, and have the properties of a local near field having high intensity and specific dispersion and surface plasmon resonance. Plasmonics is the name for the research field dealing with such surface plasmon waves, including the study of making a waveguide for the surface plasmon waves, modulating the surface plasmon waves, and studying a plasmon source and a receiver, a distributor, a coupler, a reflective lattice, a filter, etc.
Research into novel devices using surface plasmons is being conducted by many groups and the results thereof are frequently reported in prominent journals. Based on such research, plasmonics technology for focusing electromagnetic waves to a very small structure to thus transfer them is expected to lead to super high speed computer chips or super high sensitivity sensing techniques.
An optoelectronic integrated circuit module or an optical integrated circuit module, which is presently available, is constructed to have an area ranging from ones to tens of cm2. For example, an OADM (optical add/drop multiplexer) module has an area of ones of cm×ones of cm, and a photonic crystal integrated circuit module has at least an area of ones of mm2 (ones of mm×ones of mm).
However, the OADM module and the photonic crystal integrated circuit module do not correspond to sub-micro devices which are under active study these days, and thus cannot be applied to nano technology. Therefore, micro circuits having an area of sub-μm or less are required.